1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method, an image pickup apparatus, and a display device, and more particularly to an image processing apparatus, which is configured to generate and display a stereoscopic image that can be displayed by a conventional display device, an image processing method, an image pickup apparatus, and a display device.
2. Description of the Related Art
There has been proposed an image pickup apparatus which can divide an exit pupil of a photographing lens into a plurality of pupil areas and can simultaneously take a photograph of a plurality of parallactic images corresponding to the divided pupil areas.
U.S. Pat. No. 4,410,804 discloses an image pickup apparatus using a two-dimensional image pickup element in which one microlens and divided photoelectric conversion units are formed for one pixel. The divided photoelectric conversion units are configured to receive different partial pupil areas of an exit pupil of a photographing lens through the microlens, thereby attaining pupil division. A plurality of parallactic images corresponding to divided partial pupil areas can be generated from photoelectric conversion signals from the divided photoelectric conversion units. Japanese Patent Application Laid-Open No. 2001-083407 discloses that a picked-up image is generated by adding all signals received by the divided photoelectric conversion units.
A plurality of taken parallactic images is equivalent to Light Field (LF) data which is information of a spatial distribution of light intensity and angular distribution. “Light Field Photography with a Hand-held Plenoptic Camera” by Ren Ng et al., Stanford Tech Report CTSR 2005-02, 1 (2005) discloses a refocus technology of changing an in-focus position of a picked-up image after photographing by synthesizing an image on a virtual focusing plane different from an image pickup plane using obtained LF data.
However, an exclusive three-dimensional display device and wear of exclusive glasses are required in order to perform a three-dimensional display by using a plurality of parallactic images, and there is a problem that convenience of the three-dimensional display is reduced.